1. Field of the Invention
The present invention relates to a vehicle slide door apparatus for opening and closing an opening formed on a side of a vehicle body by a slide door which moves in the front-and-rear direction.
2. Description of the Related Art
Generally, in motor vehicles such as of one-box type in the related art, an opening formed on a side of a vehicle body is opened and closed by a slide door. The slide door is adapted to be guided in the front-and-rear direction by three rails provided in parallel (for example, see JP-A-11-157339). An upper rail and a lower rail of the three rails are installed on the vehicle body and a center rail is installed on the slide door.
The upper rail and the slide door are connected by an upper arm extending substantially in the lateral direction. The upper rail extends in the front-and-rear direction along an upper side of the opening on the vehicle body and guides one end of the upper arm in the front-and-rear direction. The other end of the upper arm is fixed to a pillar portion of the slide door. One end and the other end of the upper arm are connected so as to be capable of relative rotation about a center axis extending in the front-and-rear direction, so that relative displacement of the one end and the other end is allowed when the slide door is moved in the front-and-rear direction.
The upper arm is formed with a single stopper pin which is received by a stopper member provided on the upper rail when the slide door is at the rearmost position in the movable range. Accordingly, the position of the slide door is fixed when the slide door is moved to the rearmost position.
However, in the above-described vehicle slide door apparatus, since the slide door is supported by the single stopper pin when the slide door is located at the rearmost position in the movable range, when a load is applied to the upper arm from the stopper member, relatively large moment is exerted. As described above, since the upper arm is adapted to be capable of pivotal movement in the vertical direction, there is such a problem that the upper arm pivots when a load is applied thereto and hence the entire slide door becomes unstable.
In other words, when a passenger opens the slide door, the slide door hits against the stopper member at the rearmost position in the movable range, and hence a load is applied from the stopper member to the stopper pin, which generates a moment and results in unstableness of the entire slide door.